#include<iostream>
#include<iostream>
double cube(double a);
double refcube(double &ra);
int main()
{
	using namespace std;
	double x=3.0;
	
	cout<<cube(x);
	cout<<" = cube of "<<x<<endl;
	cout<<refcube(x);
	cout<<" = cube of "<<x<<endl;
	return 0;
}

double cube(double a)
{
	a+=a*a;
	return a;
}

double refcube(double &ra)
{
	ra *=ra*ra;
	return ra;
}
